Electrochemical Cell Ceramic Membrane Mechanical Robustness

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Dense ceramic membranes used in electrochemical cells, such as batteries and fuel cells, face challenges including brittleness, poor mechanical robustness, and difficulties in providing a good three-phase boundary exchange between reactants and ionically conductive ceramic phases, limiting their application and efficiency.

Innovation Solution

The development of electrode-supported ionically conductive ceramic membranes and multiphase electrodes that integrate a ceramic material with an electronically conductive phase and interconnected pores, enhancing mechanical strength and facilitating three-phase boundary exchange, while maintaining high ionic conductivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If dense ceramic membranes are used as the primary electrolyte, then faradaic efficiency and shelf life are improved, but mechanical robustness and reliability deteriorate due to brittleness

Engineering Contradiction:
Improvefaradaic efficiency and shelf lifeVSAvoidmechanical robustness
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent combines the dense ceramic membrane with a porous substrate to form a composite structure. The porous substrate provides mechanical strength and robustness, while the dense ceramic layer maintains high faradaic efficiency and shelf life. This merging of two different materials resolves the contradiction between reliability and mechanical strength.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The invention uses a composite structure consisting of a porous substrate and a dense ceramic membrane layer. The porous substrate (e.g., sintered metal or ceramic) provides mechanical robustness, while the dense ceramic layer (e.g., Nasicon or Lisicon) provides high ionic conductivity and faradaic efficiency. This composite approach allows the system to simultaneously achieve both reliability and mechanical strength.

Inventive Principle:
Principle #40Composite materials

2Reliability

If dense ceramic membranes are used as the primary electrolyte, then faradaic efficiency is improved, but ease of manufacture deteriorates due to susceptibility to breakage

Engineering Contradiction:
Improvefaradaic efficiencyVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent merges the fragile dense ceramic membrane with a robust porous substrate to create a composite structure. This combination allows the dense ceramic layer to maintain its high faradaic efficiency while the porous substrate provides mechanical support that prevents breakage during manufacturing and handling, thereby improving ease of manufacture.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The invention applies different material properties to different parts of the electrode structure. The dense ceramic layer is applied only where ionic conductivity is needed, while the porous substrate provides mechanical strength throughout the structure. This local differentiation allows the system to achieve high faradaic efficiency without the entire structure being as fragile as pure dense ceramic.

Inventive Principle:
Principle #3Local quality

3Reliability

If Nasicon membrane thickness is reduced to achieve acceptable ionic conductivity, then ionic conductivity is improved, but mechanical strength deteriorates making the membrane too fragile

Engineering Contradiction:
Improveionic conductivityVSAvoidmechanical strength
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent combines a thin dense Nasicon ceramic layer with a porous substrate to form a composite electrode. The thin dense layer (e.g., 1-10 micrometers) provides high ionic conductivity for sodium ions, while the porous substrate provides the mechanical strength needed to prevent breakage. This merging allows the system to achieve both high ionic conductivity and mechanical strength.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The invention uses a porous substrate as the structural foundation for the dense ceramic membrane. The porous structure provides mechanical robustness while allowing ionic transport, enabling the use of very thin dense ceramic layers (1-10 micrometers) that would otherwise be too fragile to handle or install. The porous substrate acts as a mechanical scaffold that supports the thin dense layer.

Inventive Principle:
Principle #31Porous materials

4Duration of action of stationary object

If dense ceramic membranes are used, then shelf life is improved, but device complexity increases due to the need for specialized handling and assembly

Engineering Contradiction:
Improveshelf lifeVSAvoidassembly complexity
Core Design Contradiction:
Duration of action of stationary objectVSDevice complexity

Solution Approach 1:

The patent merges the dense ceramic membrane with a porous substrate to create an integrated composite structure. This integration means the dense ceramic layer is permanently bonded to the porous substrate, eliminating the need for separate handling and assembly steps. The composite structure can be manufactured as a single unit, reducing device complexity while maintaining the long shelf life benefits of dense ceramic membranes.

Inventive Principle:
Principle #5Merging (Combining)

5Strength

If porous substrates are used to support dense ceramic membranes, then mechanical robustness is improved, but manufacturing precision deteriorates due to sintering process complexity

Engineering Contradiction:
Improvemechanical robustnessVSAvoidsintering control
Core Design Contradiction:
StrengthVSManufacturing precision

Solution Approach 1:

The patent employs specific sintering parameters (temperature range of 900-1100°C, controlled atmosphere, and specific time durations) to achieve optimal bonding between the porous substrate and dense ceramic membrane. By carefully controlling these parameters, the invention achieves strong mechanical bonding while maintaining the porosity of the substrate and the density of the ceramic layer, thus balancing mechanical robustness with manufacturing precision.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach allows for the creation of more robust and efficient electrochemical cells with improved mechanical durability and three-phase boundary exchange, enabling higher energy density and longer shelf life while minimizing material costs.

Implementation Method 1

an ionically conductive membrane to conduct ions between the first and second electrodes

Methodology Applied
Scientific EffectIonic conduction: Conduction (electrical)

Implementation Method 2

provide a good three-phase boundary exchange between a reactant (which may be gaseous or liquid or a reactant dissolved in a liquid), an electronically conductive phase, and an ionically conductive ceramic solid phase

Methodology Applied
Scientific EffectElectrochemical reaction: Electrolysis

Data Source

PatentEP2394321B1Electrochemical cell comprising ionically conductive ceramic membrane and porous multiphase electrode
Publication Date: 2014.12.10 CERAMATEC INC
  • EP2394321B1 patent drawingFigure 1A~1B
  • EP2394321B1 patent drawingFigure 2
  • EP2394321B1 patent drawingFigure 3~4

AI summary

An electrochemical cell (100) in accordance with one embodiment of the invention includes a first electrode (102a) containing a first phase intermixed with a second phase and a network of interconnected pores. The first phase contains a ceramic material and the second phase contains an electrically conductive material providing an electrically contiguous path through the first electrode (102a). The electrochemical cell (100) further includes a second electrode (102b) containing an alkali metal. A substantially non-porous alkali-metal-ion-selective ceramic membrane (104), such as a dense Nasicon, Lisicon, Li β"-alumina, or Na β"-alumina membrane, is interposed between the first (102a) and second (102b) electrodes.